Expansion cutter



June 7, 1932. L. J. LOEFFELMAN EXPANS ION CUTTER Filed Jan. 30, 1930 3 Sheets-Sheet 1 J L ae/fe imam June 7, 1932- J. LOEFFELMAN EXPANSi ON CUTTER Filed Jan. 30, 1950 5 Sheets-Sheet 2 June 7, 1932. L, .1. LOEFFELMAN 1,851,928

EXPANS ION CUTTER Filed Jan. 50, 1930 5 Sheets-Sheet 3 I fitter/1 I; Figure 3 is a transverse Patented June 7, 1932 PATENT OFFICE LEO T. LOEFFELMAN, OF ST. LOUIS, MISSOURI EXPANSION ourr'rrm 7 Application filed January 30, 1930. Serial No. 424,670. 1

This invention relates to rotary cutters of the typeadapted to be expanded and embodying a body and adjustable cutters to admit of varying the effective diameter which is advantageous in a tool ofthe reamer type. V

The invention provides a tool of thecha'racter aforesaid in which all the cutters may be simultaneously adjusted, and which in cludes means for securing the cutters in the to desired adjust-ed position, said securing means being adapted to be released or made fast by movement of a single part.

While the drawings illustrate a preferred embodiment of the invention, it is to be un- T derstood that in adapting the means to meet specific needs and requirements, the design may be varied and changes in the minor details of construction may be resorted to within the scope of the invention as claimed, without-departing from the spirit thereof.

For a full understanding of the invention and the merits thereof reference is to be had to the following description and the drawings hereto attached, in which:

5 Figure 1 is a view in elevation ofthe tool body designed for a reamer, an intermediate portion of the stem being broken away and a portion at one end being in section, to show the inclined shoulder to abut the forward ends of the clamps.

Figure 2 is a view similar to Figure 1,-

partly in section and showing the relative disposition of the coordinate parts when assembled.

sectional view on the line 33 of Figure 2.

Figure 4 is a detail perspective viewof one of the cutters.

Figure 5 is a detail perspective view of one of the clamps;

Figure 6 is a fragmentary sectional view showing the means for clamping theadjusting rings.

Figure 6a is an enlarged detail sectional View on the line Goa-6a of Figure 2.

Figure 7 is a longitudinal sectional view of a modified form of tool designed for use as a counterbore, taken on the line 7-7 of Figure 9.

I Figure 8 is a transverse sectional view on the line 88 of Figure 7.

Figure 9 is a cross's'ectional view on the line 99 of Figure 7,-1ooking in the direction indicated by the arrows.

Figure 10 is a detail view of one of the clamps. V

Figure 11 is a detail perspective view of one of the cutters.

Figure 12 is a longitudinal sectional view of a modified form of tool adapted for use for milling. 2

Figure 13 is a side view of the tool body and adjusting rings, the latter being detached. I

Figure 14 is a detail sectional view on the line 1414 of Figure 12. i V

Figure 15 is a detail perspective view of a cllamp member for use with the milling too. 1

Figure 16 is a fragmentary sectional view showing the means for securing the adjusting rings associated with the cutters. V 1

Corresponding and like parts are referred to in the following. description and designatsize, depending upon the particular use. .7

The cutters are designated by the numeral 2 and are provided in pairs to permit of a single element 3 being utilized for securing a pair of cutters in the required adjusted position. Longitudinal channels 4 arevformedin the sides of the body and these channels decrease in depth toward the end of the body throughout their length as indicated most clearly in Figure 2 of the drawings.

incline and correspond totheinclination of 1 to receive the cutters 2v The inner edges of'the cutters2" the inner or bottom walls of the channels 4. The cutting edges of the cutters 2 are parallel to the axis of the body 1 and remain parallel to a given position at all adjustments. An annular groove 5 is formed in the body 1 adjacent its forward end and inclines in depth inwardly and forwardly as shown most clearly in Figure 1 of the drawings. The portion of the body between adjacent channels 1 is cut away to provide a seat 6 which is parallel to the axis of the body 1. The inclined annular groove 5 results in an inclined shoulder 7 at the forward end of the seat 6, as indicated most clearly in Figure 2 of the drawings. A clamp member 3 is associated with each of tlie seats 6 and is dis posed between the cutters 2 at the sides of the.

seat. The clamp members 3 are of wedge form in cross section and are uniform throughout the major portion of their length with the exception of an end portion which is thickened and formed upon its outer side with thread sections 8. The forward terminal of each clamp member 3 is inclined, as indicated at 9, to match the inclined shoulder 7 upon which it is adapted to ride to effect an inward movement of the clamp member when the same is forwardly adjusted. An adjusting ring 10 loose upon the body 1 is internally threaded to match the thread sections 8 and rotation of this ring effects a longitudinal movement of the clamp members 3 whereby to release the cutters or secure them, asrequired. The adjusting ring 10 abuts against a shoulder-11 formed on the body 1, thereby limiting the movement of the ring in one direction;

A second adjusting ring 12 is mounted upon the body 1 forwardly of and in contact with the adjusting ring 10 and is prevented from displacement by means of a screw13, the head of which has an eccentric arrangement to admit of binding or clamping the rings 10 and 12 to hold them in the required adjusted position. The ring 12 is internally threaded to match thread sections 14 on the shanks of the cutters 2, whereby rotation of the ring effects longitudinal movement of the cutters and lateral adjustment thereof by reason of their inner inclined edges riding upon the inclined inner or bottom walls 4 of the channels. A pair of cutters 2 and an intermediate coacting clamp member 3 constitute a group and each tool may comprise a number of groups, depending upon the diameter and specific use to which the tool is designed.

Rotation of the ring 10 in one direction moves the clamp 3 rearwardlyand releases the cutters and the latter may be adjusted by rotation of the ring 12. Reverse rotation of the ring 10 moves the clamp 3 forwardly and their beveled ends 9 riding upon the inclined shoulders 7 effect an inward movement of the clamp members, thereby binding the cutters and securing them in the required adjusted position. The screw 13 is now turned to secure the adjusting rings 10 and 12 and prevent casual movement thereof in either direction.

In the modification shown in Figure 7, and the detail views thereof, the tool is constructed particularly for use as a counter bore and comprises a hollow body 1a, formed with an outer annular flange 15 against which adjusting rings 10a and 12a abut. Channels 4a are formed in the sides of the body 1a to receive cutters 2a. Clamps 3a are associated with each pair of cutters 2a and each of these clamps comprises a screw 16 and blocks 17 and'18. The clamp screws 16 pass loosely through openings formed in the flange 15 and connect the blocks 17 and 18 in a manner to clamp the flange 15 therebetween. The blocks 17 are formed with thread sections 8a which match the internal threads of the adjusting ring 10a to admit of adjusting the clamps to release or secure the cutters, as required. Each of the clamp blocks 18 has its inner or rear side beveled as indicated at 9a, to coact with an inclined shoulder 7 a of the body 1a. Upon tightening the'screw 16 the clamp blocks 17 and 18 are drawn together and the beveled end 9a of the block 18 riding on the inclined shoulder 7 0, effects an inward movement of the clamp which binds the cutters at the sides thereof and secures the same in the desired adjusted position. Each of the cutters 2a is formed with thread sections 14av which match the screw threads of the adjusting rings 12a and rotation of this ring effects adjustment of the cutters in the manner stated hereinbefore.

The modification shown in Figure 12 and the detail views'thereof, illustrate a milling tool which includes a hollow body 1?) channeled in its outer side as indicated at 45 to provide seats for cutters 2b, the portions of the body between adjacent channels being cut away, as indicated at 6?) to receive the clamps 37). An annular groove 5?) is formed in the body 1?) adjacent an end thereof to provide the inclined shoulder 71) for the inclined or beveled end 95 of the clamp 37) to abut. One end of the body 1?) is reduced and externally threaded to receive the adjusting ring 10?) and the opposite end of the body is recessed to receive the threaded portion 20 of the adjusting ring 12?). This threaded portion 20 coacts with thread sections of the cutters 2b to admit of longitudinal adjustment of the cutters in their channels 1?). The adjusting ring 12b is formed with an annular groove 21 in which is received the head of a clamp screw 13?) threaded into the body 1?). and in this manner the ring 12?) is made secure in the required adjusted position.

One end of the clamp 3b is beveled or inclined, as indicated at 9?), and an inclined lug 22 projects laterally therefrom adjacent the opposite end to engage an inclined shoulder 23 formed by grooving the ring 10?). In this manner, the clamp 36 is adapted to be drawn inwardly at each end by reason of the inclined shoulders 23 and 7b. Rotation of the ring 10?) in one direction, releases the clamp 31) so that the cutters may be adjusted by rotation of the ring 125 and after adj ustment has been effected, the cutters are made secure by a reverse rotation of the ring 10?) which moves the clamp inwardly and binds the cutters by a wedging action, as will be readily appreciated.

What is claimed is:

1. An expansion tool comprising a body having an annular shoulder, an annular groove spaced from said shoulder longitudinally of the body and inclined inwardly toward the end of the body and pairs of longitudinal channels in its outer side with the portions between the channels of each pair cut away, said groove defining inclined shoulders at the outer ends of said cut away portions, cutters seated in the channels, clamps seated in the cut away portions of the body between the cutters and each having an end beveled to engage the inclined shoulder formed by said groove, and adjusting rings engaged with the cutters and clamps, the ring engaged with the clamps abutting the firstmentioned annular shoulder on the body and the ring engaged with the cutters abutting the first-mentioned ring, rotation of the rings effecting longitudinal and radial movement of the cutters and the clamps for securing the same.

2. An expansion tool comprising a body provided near one end with an annular shoulder inclined inwardly toward said end and provided at a point remote from said end with an annular radial shoulder, cutters seated in the side of the body, means for adjusting the cutters, clamps seated in the side of the body between and bearing upon the sides of the cutters, each clamp having one end beveled to engage under the inclined shoulder on the body and its opposite end externally threaded, and an internally threaded adjusting ring abutting the radial shoulder on the body and engaging the threaded ends of the clamps.

3. An expansion tool comprising a body having longitudinal radial channels in its side, said channels decreasing in depth toward the outer end of the body and the portions of the body between the channels being cut away, an inclined annular shoulder on the body near the outer end thereof, a radial annular shoulder on the body near the inner ends of the channels, cutters seated in the channels and having externally threaded inner ends, clamps seated in the cut away portions of the body between and bearing upon the sides of the cutters, each clamp having a threaded ends of the clamps, an internally threaded adjusting ring abutting the firstmentioned ring and engaging the threaded ends of the cutters, and means for resisting movementof the rings from the radial shoulder on the body.

In testimony whereof I afiix my signature.

LEO J. LOEFFELMAN. [n 5. 

